Add AsCommand rector

[glensc]

Similar to Symfony rectors

        \Rector\Symfony\Symfony61\Rector\Class_\CommandPropertyToAttributeRector::class,
        \Rector\Symfony\Symfony61\Rector\Class_\CommandConfigureToAttributeRector::class,

• https://getrector.com/rule-detail/command-property-to-attribute-rector
• https://getrector.com/rule-detail/command-configure-to-attribute-rector

Symfony commands have:

    protected $signature = '...';
    protected $description = '...';

[calebdw]

I like this! I'll try to work on this soon. There will be some difficulty in doing this though if the signature contains additional options/arguments instead of using get{Arguments,Options}